1. Field of the Invention
This invention relates generally to a differential mechanism and, in particular, to an adjuster for locating a carrier relative to a housing, and for producing and maintaining preload on bearings in the differential mechanism.
2. Description of the Prior Art
The bearings that support a differential carrier in an axle differential are commonly preloaded by shims, snap rings, or adjuster nuts.
These devices, which position the differential carrier and preload the bearings, affect bearing life, heat generation, operating efficiency and system stiffness. Of the three devices, use of adjuster nuts provides the easiest method for locating the differential carrier and setting the bearing preload at its initial installation and later while in service. In contrast to shims and snap rings, releasing the locking mechanism allows a simple rotation of the adjuster nut to correct preload and position issues.
Shims and snap rings involve spreading the housing, removing the old shim or snap ring, and installing new ones.
Despite the advantages of adjuster nuts, the usual method of forming the adjuster threads into a split bore created by a cap and housing creates manufacturing and assembly problems. Creating a large diameter, fine pitch thread in the housing and cap, or in the housing alone increases the opportunity for cross threading, cap misalignment, and related scrap issues.